Patent · US Expired

Vacuum delay/relief valve

US4010721A · kind A · utility

8Cited by
5References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 24, 1975
Grant dateMar 8, 1977
Priority date
Expiry dateApr 24, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7847
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A device for use in an internal combustion engine for reducing emissions and for improving engine performance and economy having valve means for restricting air flow from the carburetor spark port to the vacuum advance cylinder at moderate acceleration to delay spark retard and for permitting unrestricted air flow at substantially full throttle acceleration to provide normal spark retard.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.